Adding-machine dash-pot mechanism.



I. A. NIE'MANN.

ADDING MACHINE DASH POT MECHANISM. APPLICATION FILED APR.27, 1908.

4 SHEETS-SHEET 1.

Patented Dec. 26, 1911.

F. A; NIEMANN.

ADDING MACHINE DASH POT MECHANISM.

. APPLICATION FILED APR. 27, 1908. 1,012,698. Patented Dec. 26, 1911..

4 SHEETSSHEET 2.

, jarluy/cvwc, J

P. A. NIEMANN.

ADDING MACHINE DASH POT MEGHA NISM. APPLICATION FILED APR.27, 1908.

1,012,698. Patented Dec.26, 1911.

4 SHEETS-SHEET 3 /7/ W1/. 19?} u I; gm,

F. A. NIEMANN.

ADDI NG MACHINE DASH POT MECHANISM. APPLICATION FILED APR.27, 1908.

4 SHEETSSHBBT 4 Patented Dec. 26, 1911.

UNITED STATES PATENT OFFICE.-

FREDERICK A. NIEMANN, OF CI-IICAGO,' ILLINOIS, ASSIGNOR- 'I'O COMPTOGRAI'H COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

ADDING-MACHINE DASH-POT MECHANISM.

Specification of Letters Patent.

Patented Dec. 26, 1911.

To all whom it may concern:

Be it known that I, FREDERICK A. NIE- MANN, a citizen of the United States, residing in Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Adding-Machine Dash-Pot Mechanism, of which the following is a specification.

My invention relates to improvements in adding machine mechanism, and particularly to that of printing machines, whereby the speed of movement of the actuating rock-shaft or rock-shafts of the machine will be most eiiectively governed and graduated to properly check and cushion the rapidly moving parts and yet reduce to a minimum the resistance opposed "to the hand of the operator or to any motor drive mechanism that may be substituted for hand operation of the machine, and the invention specially relates to the daslrpot device commonly 'embodied in such printing adding machines to govern and limit the rapid movement of their parts.

The invention is shown as embodied in the well known Comptograph printing adding machine, generally shown in the U. S. patent to Felt et al, No. 853543, and other prior patents to Felt; and the aforesaid dash-pot mechanism heretofore employed in such machines is shown more particularly on Sheet 5 of the drawings of said Patent 853543.

In the accompanying drawings, forming a part of this specification, Figure lis a vertical longitudinalsection of the entire adding machine, such as is shownin the aforesaid Patent 8535543; Fig. 2 is a side elevation of the same machine, showing the dash-pot in its operative relation to the main actuating rock-arms and rock-shafts whereby movement is imparted to the adding and printing mechanisms; Fig. 3 is a vertical sectional view of the improved dash-pot; Fig. 4 is a sectional view on the .line 44 of F ig. 3; Fig. 5.is a side elevation of the adding machine; and Fig. 6 is a partial side elevation showing the parts in different positions from those occupied in Fig. l.

.Like reference numerals indicate like parts in all the figures. Figs, 5 and 6 are exact duplicates of Figs. 1 and 2, respectively, of the above mentioned Patent No. 853,543, and are.

operatipn of the addingand-printing mech- 211118111, in the manner set forth in the above mentioned Letters Patent, including a consecutive series of diverse movements timed tooccur during the oscillation of the said rock-shaft. oscillation of said secondary rock-arm and rock-shaft, said secondary rock-arm is linked,- by the connection 16, .with the further rock-arm 17 secured on the rockshaft 18, to which rock-shaft are also secured the rock-arms 19 to whose free ends the dash-pot cylinder 20 is pivotally at: tached. The dash-pot piston 21 is secured on the lower end 0 the piston-rod 22, and the upper end of said piston-rod 22 is pivotally swun'g on the pivot 23. It is obvious that as the rock-shafts oscillate the dashpot cylinder will be reciprocally'raised and lowered in relation to the piston, the pistonrod swinging back and forth on its pivot, all in the manner particularly set forth on page 8 of the specification of the aforesaid Patent 853543. And, as the cylinder re- And to govern and control the ciprocates, the oil or other resistant liquid in the dash-pot will flow from one side of the piston to the other, around such piston and through the ports 24 and 25 that penetrate said piston, the check plate 26 and the ball valve 27 retarding such flow during the upstroke of the cylinder, such ball valve dropping to open the port 24 during the down stroke of the cylinder, in the manner described in the aforesaid Patent- 853543.

But in the mechanism of my present invention I have provided a check-rod 28 having its opposite ends rigidly fixed in the op;- posed heads of the dash-pot cylinder, and

passing freely through the port 25 in the piston and an aperture 29 in the checkplate 26 immediately above said piston-' port; and intermediate the llmits of the stroke ofthe piston up and-down a part of its length this check-rod is reduced in diameter, at 30, so that While the piston is passing over such reduced portion of said 5, check-rod the port 25 will ofler an increased free aperture for the flow of the resistant oil from one side of the piston to the other.

And at either end, and ithin the limit of the pistons stroke, such reduced portion ofithebheck-rod is tapered out, at 31 and 32, to the full diameter of said. check-rod, so that at the limit of the pistons stroke the said check-rod will nearly close the aforesaid port 25. By this device it is obvious that'the piston will be cushioned to the maximum extent at either limit of its stroke but be relatively free throughout the intermediate period of said stroke. And the practical result of thus varying the resis tance that the dash-pot oflers to the movement of the actuating rock-shafts of the adding machine, is to provide an effective cushioning of such movement at either limit of each back and forth movement of the operating handle of the main rock-shaft and yet reduce theresistance to movement during the intermediate period of each stroke. In this manner any shock or jar may be efl'ectively prevented at the limit of the forward pull of the operating handleor rock-shaft, and yet the reduction of the resistance ofl'ered by the dash-pot during the antecedent period of the stroke will substantially lighten and lessen the pull by which the adding machine is actuated. The adding machine may thus be operated with less exertion on the part of the operator, or less strain on any motor-drive device that is substituted for hand operation; and yet the machine is still efiectively protected against shock or jar resulting from either a violent forward jerk' of the operating handle, or its shaft, or the violent backward jerk that results when the adding machine is locked and the main rockshaft is rocked and released under the tension of the fnain spring-connection.-

My invention is hereinabove set forth as embodied in one particular form of construction, but I do not limit it thereto or to less than all the possible forms wherein the said invention as hereinafter claimed may be embodied and distinguished from prior devices for like purpose.

55 I claim 1. In a printing adding-machine, in combination, adding and printing mechanism, an actuating rock-shaft therefor, operating connections between said mechanism and said rock-shaft, such operation of the adding-and-printing mechanism including a consecutive serles of diverse movements timed to occur during the oscillation of the said rock-shaft, and a dash-pot for govern.

ing the operatlolroit said connections, said l ases dash-pot being internally provided with means for automatically varying, during each strokeof the piston in each direction, an aperture through which the resistant liquid flows from one side of the piston to the other, whereby a varying resistance. and cushioning of said piston is efiected, accommodating the varying resistances of the consecutive series of diverse movements in said adding-and-printing mechanism, substantially as specified.

2. In a printing adding-machine, in combination, adding and printing mechanism, an actuating rock-shaft therefor, operating connections between said mechanism and said rock-shaft, such operation of the'adding-and-printing mechanism including a consecutive series of diverse movements timed to occur during the oscillation of the said rock-shaft, and a dash-pot for governing the operation of said connections,'said dash-pot being internally provided with a fixed check-device for au atically varying, during each stroke of e piston in each direction, an aperture through which the resistant liquid flows from one side of the piston to the other, whereby a varying resistance and cushioning of said piston is efiected,accommodating the varying resistances of the consecutive series of diverse movements in said adding-and-printing mechanism, substantially as specified.

3.. In a printing-adding machine,in' combination, adding and printing mechanism, anactuating rock-shaft therefor, operating connections between said mechanism and said rock-shaft, suchoperation of the adding-and-printing mechanism including a w consecutive series of diverse movements timed to occur during the oscillation of the said rock-shaft, and a dash-pot for governing the operation of said connections, said dash-pot being internally provided with a fixed check-rodpassing' transversely through.

a port in the piston, ,said check-rod being reduced for a part of its length intermediate the limits of the reciprocation of the piston, 7 whereby the flow of the resistant liquid through said port, from one side of the piston to the other, is automatically varied during each piston-stroke, tovary the resistance and cushioning of the piston, accommodating the varying resistances of the consecutive series of diverse movements in'said adding-and-printing mechanism, substantially as specified.

4. In a printing-adding machine, in combination, adding and prlnting mechanism, an actuating rock-shaft therefor, operating connections between said mechanism and 126 said rock-shaft, such operation of the adding-and-printing mechanism including a consecutlve serles of diverse movements timed to occur during the oscillation of the I said-rock-shaft, and-a dash-pot for govern- 1 30 ing the operation of said connections, said dash-pot being internally provided With a fixed check-rod passing transversely through a port in the piston, said check rod being reduced and tapered for a part of its length intermediate the limits of the reciprocation of the piston, whereby the flow of the resistant liquid through said port, from one side of the piston to the other, is automatically varied during, each piston-stroke, to vary the resistance and cushioning of the piston,

accommodating the varying resistances of the consecutive series of diverse movements in said adding-and-printing mechanism, substantially as specified.

In testimony whereof I have hereunto set my hand in the presence of two subscribing Witnesses.

FREDERICK A. NIEMANN. Witnesses:

HENRY LOVE CLARKE, HARRY B. WYETH. 

